Many surgical instrument cleaning chemistries contain corrosion inhibitor ingredients and chelating agents to help mitigate the damaging effects of water on surgical instrumentation and washing equipment.
Control of corrosion in surgical instruments and utensil processing is critical in maintaining the safe and effective operation of said devices. Many instruments and utensils contain soft metals such as copper, brass, aluminum and anodized aluminum. These soft metals are very susceptible to damage from both the detergents and the water in which they are processed. Typically neutral cleaning chemistries are used to process these metals. The neutral chemistries often contain silicate corrosion inhibitors that render them unusable for specific applications. They can also contain non-environmentally friendly corrosion inhibitors that create disposal concerns.
Heretofore, scale control has been achieved by using either a chelant or a scale inhibitor. Chelants such as EDTA (ethylene diamine tetraacetic acid), NTA (nitrilotriacetic acid), phosphates, and phosphonates inhibit calcium and magnesium scale by chemically binding to the calcium or magnesium ions in a one to one molar ratio. EDTA, NTA, and many other traditional chelants and scale inhibitors are not environmentally friendly. Additionally, the usage levels in concentrated detergents are generally 10% or greater, increasing their negative impact. Scale inhibitors such as polyacrylic acid inhibit the crystal structure of calcium carbonate, preventing the calcium carbonate salts from aggregating into particles large enough to precipitate.
U.S. Pat. No. 6,846,793 relates to compositions of the invention include: a surfactant having an HLB value from 1 to 10; and a compound of formula (I):
where; x is an integer from 2 to 6, y is an integer from 0 to 5, R is a bond or (C1-C4)alkylene, R1 is a hydrogen, halo, aryl, (C1-C4)alkyl, heteroaryl, cycloalkyl, or heterocycyl, and R2 is independently selected from hydrogen, halo, (C1-C4)alkyl, (C1-C4)alkoxy, (C2-C4)alkenylene.
U.S. Pat. No. 6,686,325 relates to an alkaline sensitive metal cleaning composition. The alkaline sensitive metal cleaning composition contains an alkaline concentrate and a corrosion inhibitor concentrate. The alkaline concentrate includes a source of alkalinity in an amount sufficient to provide a use solution having a pH of at least 10.0, and a first chelant component that exhibits soil removal properties when used at a pH of at least 10.0. The corrosion inhibitor concentrate includes a corrosion inhibitor component for reducing corrosion of alkaline sensitive metals when used in a use solution having a pH of at least 10.0, a second chelant component for stabilizing the corrosion inhibitor in the corrosion inhibitor concentrate when the corrosion inhibitor concentrate is provided at a pH that is less than 8.0, and a surfactant component for providing cleaning properties when used at a pH of at least 10.0.
U.S. Pat. Nos. 7,597,766, 7,642,224, and 7,648,583 relate to an aqueous, concentrated neutral detergent composition for use in cleaning medical instruments and metal components (parts, tools, utensils, vessels, equipment, and surfaces) having scale control and corrosion inhibition properties when diluted to about 1/40 ounce per gallon to about 1/10 ounce per gallon in potable water. In addition, the concentrate may be applied directly to metal surfaces, such as stainless steel, to remove rust and other stains, without causing any additional corrosion or other damage to the metal surface.
U.S. Publication 2008/0108539 relates to corrosion inhibitor systems, in particular to cleaning and corrosion inhibiting compositions for surfaces of aluminum or colored metals and alloys thereof under alkaline conditions, especially in the food and pharmaceutical industries. The cleaning and corrosion inhibiting compositions comprise as a corrosion inhibitor at least one alkyleneoxy alkylphosphate di- or triester having the general formula as set forth therein.
U.S. Publication 2008/0221006 relates to an aqueous, alkaline cleaning composition comprising a source of alkalinity, a biodegradable surfactant system further comprising one or more surfactants, one or more hydrotropes, and a UV-analyzable surfactant, and a biodegradable chelating agent.
U.S. Publication 2009/0298738 relates to an alkaline concentrated detergent composition for use in cleaning hard surfaces, medical instruments and other metal components (parts, tools, utensils, vessels, equipment) having cleaning efficacy at much lower alkali content than traditional alkaline cleaners and enhanced scale control properties even when diluted to about 1/40 ounce per gallon to about 1/10 ounce per gallon in potable water and even in exceptionally hard water.
WO 2009/125335 relates to a substantially nonaqueous concentrated composition comprising an amine oxide surfactant, a water-soluble solvent, a source of alkalinity, a chelating agent and a hydrotrope wherein the concentrate composition is useful in preparing a water soluble solution. The composition may optionally include any one or combination of a nonionic surfactant, anionic surfactant, a corrosion inhibitor, dye, perfume, or preservative.
WO 2009/125336 relates to a substantially nonaqueous solid concentrated composition comprising an amine oxide surfactant, an alkali metal hydroxide, a secondary source of alkalinity, a chelating agent, a nonionic surfactant, and a hardening agent wherein the concentrated composition is useful in preparing an aqueous solution. The composition may optionally include any one or combination of an anionic surfactant, a corrosion inhibitor, dye, perfume, or preservative. The ultra-concentrated composition of the invention is suited for solid deliveries.